1. Technical Field
The present invention relates to a physical quantity sensor and an electronic apparatus.
2. Related Art
Recently, physical quantity sensors such as inertial sensors have been developed which detect a physical quantity, for example, using silicon MEMS (Micro Electro Mechanical System) techniques.
For example, JP-A-2008-529001 discloses a seesaw physical quantity sensor that detects acceleration in a Z axis direction using an oscillating motion (seesaw oscillation). The physical quantity sensor disclosed in JP-A-2008-529001 includes a conductive plate and a proof mass having first and second regions which are different in mass from each other. The proof mass oscillates around an oscillation axis, which partitions the first and second regions, depending on the acceleration in the Z axis direction. The physical quantity sensor disclosed in JP-A-2008-529001 detects the acceleration on the basis of a variation in capacitance between the conductive plate and the proof mass, which results from oscillation of the proof mass.
The physical quantity sensor disclosed in JP-A-2008-529001 includes a protective shield used to limit the oscillation of the proof mass and a stopper protruding to the protective shield. Accordingly, it is possible to prevent the conductive plate and the proof mass from coming in contact with each other, thereby enhancing reliability.
However, in the physical quantity sensor disclosed in JP-A-2008-529001, the stopper has to be formed by depositing and patterning a predetermined material on the proof mass, thereby causing complication of manufacturing processes thereof.